books = ["Pride and Prejudice", "Ulysses", "To Kill A Mockingbird", "Charlotte's Web"]
#1.统计书籍总数
count = len(books)
print(f"共有{count}本书")
#2.添加书籍
books.append("Bridge to Terabithia")
print(books)
#3.按字母顺序排序
books.sort()
print(books)
#4.删除已存在的书籍
if "Pride and Prejudice" in books:
  books.remove("Pride and Prejudice")
else:
  print("这本书不在书籍列表中！")
#5.删除书籍（clear）
books.clear()
print(books)

